Multi QWs for laser diodes with emission wavelengths above 1100 nm

Published in:
Proc. 11th European Workshop on Metalorganic Vapour Phase Epitaxy, June 2005, Lausanne, Switzerland, F06, p. 299-301.
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Introduction:
Due to their high output power potential GaAs based laser diodes in the wavelength range at and beyond 1100 nm are interesting as pump sources for Raman amplifiers in telecommunication systems, for pumping up-conversion fiber lasers or direct material processing without transfer of optical power to fibers or solid state lasers [1]. In comparison to AlGaAs, GaAs waveguides offer lower series resistance and higher thermal conductivity which reduces resistive heating and facilitates the removal of heat from the active region. However, a severe problem is the low effective electron barrier between InGaAs quantum well (QW) and GaAs waveguides which leads to low internal efficiency. An increase of the number of QWs should result in an increased internal efficiency. Therefore, such structures have the potential for a very high optical output power [2]. AlGaAs/GaAs test and laser structures with highly strained InGaAs QWs were grown and the effect of different numbers of QWs on layer properties and laser performance was investigated.

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